1. Field of the Invention: The present invention relates, in general, to a system for closing fire doors that can be quickly and easily tested by merely moving a test handle to a test position, and that can be quickly and easily reset by merely moving the fire door back to an opened position and moving the test handle back to a set position.
2. Information Disclosure Statement: Fire doors that close automatically in the event of a fire or other predetermined occurrence are well known in the art. However, it is necessary to test such fire doors on a periodic basis to insure that they will operate correctly in the event of a fire or other predetermined occurrence. A long-standing problem with such testing is the difficulty and time-consuming nature of properly re-setting such fire doors after a test. The known prior fire door closure systems require substantial time, know-how, and skill to restring cables, reattach fusible links, etc., in order to reset the system after a test.
A preliminary patentablity search has been conducted in class 49, subclasses 7 and 8.
Frederick, U.S. Pat. No. 3,398,482, issued Aug. 27, 1968, and Hemmerling, U.S. Pat. No. 4,467,562, issued Aug. 28, 1984, disclose fire door closure systems that are heat responsive based on a fusible link to close a fire door or allow a fire door to close in the event of a fire. Neither Frederick, U.S. Pat. No. 3,398,482, nor Hemmerling, U.S. Pat. No. 4,467,562, disclose a means to test and reset the system other than melting or releasing a fusible link.
Wescoat et al., U.S. Pat. No. 4,648,310, issued Mar. 10, 1987, discloses an apparatus for causing a curtain or the like to move to a closed position in the event of a fire or the like. The Wescoat et al. apparatus includes a manual release arm for allowing the system to be manually activated. However, once manually activated, substantial work and repair will be required to reset the system. Thus, for example, the glass face of a box would have to be replaced, and at least one worker would most likely be required to properly position the manual release arm and a plurality of linkage arms and the like while another worker properly positioned the pull ring within the box, etc.
The present invention is directed toward providing a fire door closure system that can be tested by merely moving a test handle to a test position, and that can be reset by merely moving the fire door back to an opened position and moving the test handle back to a set position. None of the above patents disclose or suggest a closure reset system including a fire door movable between an opened position and a closed position relative to an opening through a wall; lock means for being pivotally attached relative to the wall for movement between a locked position and an unlocked position and for allowing the fire door to move to the closed position when in the unlocked position; urging means for urging the lock means to the unlocked position; a cable having a first end for being attached to the lock means and having a second end for being fixedly attached relative to the wall; the lock means being held in the locked position when the cable is taut; the urging means urging the lock means to the unlocked position when slack is placed in the cable; occurrence responsive mean for placing slack in the cable in the event of a predetermined occurrence; and test-reset means for allowing the operation of the fire door closure reset system to be tested by placing slack in the cable and for allowing the slack in the cable to be subsequently removed after the operation of the fire door closure reset system is tested to reset the fire door closure reset system.